Microtunnel Under Grand Union Canal Will Power HS2 TBMs

A microtunnel that will carry power cables for HS2 TBMs is to be constructed under the Grand Union Canal in London ahead of the building of the Euston section.

A microtunnel that will carry power cables for HS2 boring machines is to be constructed under the Grand Union Canal in London. New Civil Engineer reports that a 1,500mm diameter concrete tunnel is being constructed from pre-cast concrete sections.

The HS2 tunnel boring machines (TBMs) will be used to build tunnels for the section of the line between Old Oak Common and Euston Station. The microtunnel will be 125m long, with shafts of 6m diameter and 15m depth. The government is currently seeking private investment for the construction of a new HS2 station at Euston.

The power cable tunnel project will be carried out by UK Power Networks in partnership with Barhale.

UK Power Networks capital programme manager Pamela Ali said: “It has been a huge achievement to successfully and safely construct the micro-tunnel which will enable to install our circuits across the Grand Union Canal. A huge thank you to the HS2 and the Canal & River Trust for their support throughout.”

HS2 head of utilities Niki French said: “The delivery of this power tunnel is a critical part of our programme to build the new high-speed railway into the heart of London. Through close collaboration and great teamwork, we have worked together to ensure the HS2 programme is maintained.”

Elsewhere, the government has set out plans to progress the Northern Powerhouse Railway (NPR) between Liverpool and Manchester. The Department for Transport (DfT) has confirmed that the plans will go ahead after the section of the HS2 railway north of Birmingham was cancelled.

However, the original scope of the NPR has already been scaled back due to budget constraints. In 2015, the DfT announced plans for a high speed line that would connect all of the major northern cities between Liverpool and Hull. This was revised in 2021, with a commitment only to the sections between Liverpool, Manchester and Leeds.

The DfT has now committed £12bn investment in the first section of the railway, with the proposed route between Warrington Bank Quay and Manchester Airport. Ultimately, this should cut the journey time between Liverpool and Manchester from 50 minutes to 35 minutes, and there will be trains running at least every 20 minutes.

In his statement to Parliament, transport secretary Mark Harper said: “There is also interest from local leaders in exploring further options for station design at Manchester Piccadilly and for routings into Liverpool including station options.”

“Government remains open to considering these issues, subject, as usual, to affordability within the funding envelope, standard business case approvals and demonstrating value for taxpayers’ money. I look forward to continuing discussions on these points.”

“Recognising the consensus reached, I am today (25 March 2024) confirming that this will represent the basis for the next stage of development. As with any major scheme, delivery will be subject to securing consent and the approval of future business cases.”

If the section of the railway between Manchester and Leeds also goes ahead, it is estimated that this will triple the current passenger capacity between Liverpool and Leeds.